// Copyright 2014 The Chromium Authors. All rights reserved.
// Use of this source code is governed by a BSD-style license that can be
// found in the LICENSE file.

#ifndef CONTENT_BROWSER_ANDROID_OVERSCROLL_CONTROLLER_ANDROID_H_
#define CONTENT_BROWSER_ANDROID_OVERSCROLL_CONTROLLER_ANDROID_H_

#include <memory>

#include "base/android/scoped_java_ref.h"
#include "base/macros.h"
#include "base/time/time.h"
#include "content/common/input/input_event_ack_state.h"
#include "ui/android/overscroll_glow.h"
#include "ui/android/overscroll_refresh.h"
#include "ui/gfx/geometry/vector2d_f.h"

namespace blink {
class WebGestureEvent;
}

namespace cc {
class CompositorFrameMetadata;
class Layer;
}

namespace ui {
class WindowAndroidCompositor;
struct DidOverscrollParams;
}

namespace content {

// Glue class for handling all inputs into Android-specific overscroll effects,
// both the passive overscroll glow and the active overscroll pull-to-refresh.
// Note that all input coordinates (both for events and overscroll) are in DIPs.
class OverscrollControllerAndroid : public ui::OverscrollGlowClient {
public:
    OverscrollControllerAndroid(
        ui::OverscrollRefreshHandler* overscroll_refresh_handler,
        ui::WindowAndroidCompositor* compositor,
        float dpi_scale);
    ~OverscrollControllerAndroid() override;

    // Returns true if |event| is consumed by an overscroll effect, in which
    // case it should cease propagation.
    bool WillHandleGestureEvent(const blink::WebGestureEvent& event);

    // To be called upon receipt of a gesture event ack.
    void OnGestureEventAck(const blink::WebGestureEvent& event,
        InputEventAckState ack_result);

    // To be called upon receipt of an overscroll event.
    void OnOverscrolled(const ui::DidOverscrollParams& overscroll_params);

    // Returns true if the effect still needs animation ticks.
    // Note: The effect will detach itself when no further animation is required.
    bool Animate(base::TimeTicks current_time, cc::Layer* parent_layer);

    // To be called whenever the content frame has been updated.
    void OnFrameMetadataUpdated(const cc::CompositorFrameMetadata& metadata);

    // Toggle activity of any overscroll effects. When disabled, events will be
    // ignored until the controller is re-enabled.
    void Enable();
    void Disable();

private:
    // OverscrollGlowClient implementation.
    std::unique_ptr<ui::EdgeEffectBase> CreateEdgeEffect() override;

    void SetNeedsAnimate();

    ui::WindowAndroidCompositor* const compositor_;
    const float dpi_scale_;

    bool enabled_;

    // TODO(jdduke): Factor out a common API from the two overscroll effects.
    std::unique_ptr<ui::OverscrollGlow> glow_effect_;
    std::unique_ptr<ui::OverscrollRefresh> refresh_effect_;

    DISALLOW_COPY_AND_ASSIGN(OverscrollControllerAndroid);
};

} // namespace content

#endif // CONTENT_BROWSER_ANDROID_OVERSCROLL_CONTROLLER_ANDROID_H_
